In the future, Ford envisions customers using 3D printers to get on-demand replacement parts for their cars. But for now the car company uses the technology to make prototypes parts, which makes the testing process more efficient.

Using 3-D printing, Ford saves an average of one month of production time to create a casting for a prototype cylinder head for its EcoBoost family of engines, designed for better fuel efficiency. This complex part includes numerous ports, ducts, passages and valves to manage fuel and air flow.

The traditional casting method takes four to five months. With 3D printing it takes three.

General Electric

For GE, 3D printing isn't just helping in the design process. Soon, you might be flying in a plane with a motor made with parts that were 3D printed.

The toy company used to create product prototypes from wax and clay. The process is much more efficient now that Mattel engineers have turned to 3D printing for parts of "virtually every type of toy that it manufactures."

But don't expect the company to roll out any 3D printing toy kiosks anytime soon, according to WSJ. It might give customers the idea of designing their own toys.

All three of these companies are showing the way for a manufacturing and design future that will increasingly rely on 3D printers. According to a recent report from Wohlers Associates, it took the industry 20 years to become a $1 billion a year industry, but only took five years to add the second billion. Now, as of 2012, the industry has reached $2.2 billion with 29 percent growth. That growth is expected to continue as the industry is predicted to reach $6 billion by 2017.